1. Field of the Invention
The present invention relates to a vehicle surroundings monitoring apparatus which detects a monitored object existing around a vehicle from images obtained by a camera mounted on the vehicle and monitors the surroundings of the vehicle.
2. Related Background Art
Conventionally, there has been suggested a vehicle surroundings monitoring apparatus which has two cameras mounted on a vehicle and detects a distance between a monitored object and the vehicle by the principle of triangulation based on a difference (parallax) between image portions of the identical monitored object extracted from images of the surroundings of the vehicle taken by the cameras (for example, refer to Japanese Patent Laid-Open No. 2001-6096).
According to the conventional vehicle surroundings monitoring apparatus, the distance between the monitored object around the vehicle and the vehicle is calculated. Then, the vehicle surroundings monitoring apparatus finds a movement vector of the monitored object in a real space by converting the position of the monitored object from the image coordinates to real space coordinates based on the distance and determines whether there is a possibility of contact between the monitored object and the vehicle.
Where the distance between the vehicle and the monitored object is detected based on the parallax in this way, however, there has been a problem of an increase in cost caused by provision of two cameras and requiring a complicated work for installation such as strict adjustments of optical axes of these cameras.
Therefore, it is an object of the present invention to solve the above problem and to provide a vehicle surroundings monitoring apparatus capable of determining whether there is a possibility of contact between a monitored object around a vehicle and the vehicle with a simple arrangement in which the vehicle is provided with a single camera.